pytorch图

计算图

import  torch

w = torch.tensor([1.],requires_grad=True)
x = torch.tensor([2.],requires_grad=True)

a = torch.add(w,x)
a.retain_grad()
b = torch.add(w,1)
y = torch.mul(a,b)

y.backward()
print(w.grad)
print(a.grad)

动态图